What are the risks associated with In Vitro Fertilization (IVF) during pregnancy?

Risks Associated with IVF Pregnancies

IVF pregnancies carry increased risks of preterm birth, low birthweight, placenta praevia, and multiple pregnancies compared to spontaneously conceived pregnancies. 1

Maternal Risks

Multiple Pregnancy Risk

• Multiple pregnancy is the most significant risk of IVF and carries substantial maternal and fetal morbidity
• Risk factors for multiple pregnancy include:
  • Transfer of multiple embryos (especially two or more blastocysts) 2
  • Use of gonadotropins at doses higher than 75 IU 2

Obstetrical Complications

• Increased risk of placenta praevia and third-trimester bleeding with fresh embryo transfers 3
• Higher risk of thromboembolic events, especially when high estradiol levels are present during ovarian stimulation 2
• Potential for ovarian hyperstimulation syndrome when using gonadotropins, particularly at higher doses 2

Fetal and Neonatal Risks

Perinatal Outcomes

• Singleton IVF pregnancies have:
  • Higher rates of preterm birth (approximately 1.5 times higher than naturally conceived pregnancies) 2
  • Increased risk of low birthweight even in singleton pregnancies 1
  • Possible increased risk of stillbirth requiring antenatal surveillance 1

Birth Defects and Genetic Concerns

• Genetic counseling should be offered to all patients undergoing IVF 1
• Detailed fetal anatomic survey and fetal echocardiography are recommended for IVF pregnancies 1

Risk Mitigation Strategies

Embryo Transfer Recommendations

• Elective single embryo transfer (eSET) is strongly recommended to reduce multiple pregnancy risk 2
• Blastocysts should be transferred as single embryos due to higher implantation potential and increased risk of monozygotic twinning 2
• Consider patient-specific factors when determining number of embryos to transfer:
  • Maternal age
  • Embryo quality
  • Previous failed cycles
  • Patient preferences regarding family building 2

Monitoring Recommendations

• Weekly antenatal fetal surveillance beginning by 36 weeks gestation 1
• Third-trimester growth assessment 1
• Detailed ultrasound examination with careful assessment of placental location and cord insertion 1
• Evaluation for vasa previa due to increased risk 1

Special Considerations

Frozen vs. Fresh Embryo Transfer

• Frozen-thawed embryo transfers are associated with higher mean birth weights compared to fresh transfers 3
• Fresh embryo transfers have higher rates of placenta praevia and third-trimester bleeding 3

Medical Conditions

• For patients with cardiac conditions, IVF may be considered when the risk of the procedure and pregnancy is low 2
• Thromboembolic risk should be carefully assessed, especially with high estradiol levels 2

Patient Counseling Points

• Discuss both medical and psychological consequences of multiple pregnancy risk 2
• Explain the increased risks of preterm birth and low birthweight even in singleton IVF pregnancies 2, 1
• Inform patients about the availability of prenatal genetic screening and diagnostic testing options 1
• Consider shared decision-making regarding timing of delivery, with potential consideration of induction at 39 weeks 1

IVF remains a valuable treatment for infertility, but patients should be fully informed about the associated risks to make appropriate decisions about their care and to allow for proper monitoring during pregnancy.